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Q9XYQ1 · ITPK1_ENTH1

Function

function

Kinase that can phosphorylate various inositol polyphosphate such as Ins(3,4,5,6)P4 or Ins(1,3,4)P3. Phosphorylates Ins(3,4,5,6)P4 at position 1 to form Ins(1,3,4,5,6)P5. This reaction is thought to have regulatory importance, since Ins(3,4,5,6)P4 is an inhibitor of plasma membrane Ca2+-activated Cl- channels, while Ins(1,3,4,5,6)P5 is not. Also phosphorylates Ins(1,3,4)P3 on O-5 and O-6 to form Ins(1,3,4,6)P4, an essential molecule in the hexakisphosphate (InsP6) pathway. May also act as an isomerase that interconverts the inositol tetrakisphosphate isomers Ins(1,3,4,5)P4 and Ins(1,3,4,6)P4 in the presence of ADP and magnesium.

Catalytic activity

Cofactor

Mg2+ (UniProtKB | Rhea| CHEBI:18420 )

Note: Binds 2 magnesium ions per subunit.

Features

Showing features for binding site.

TypeIDPosition(s)Description
Binding site171D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site171D-myo-inositol 1,3,4-trisphosphate (UniProtKB | ChEBI)
Binding site571D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site94ADP (UniProtKB | ChEBI)
Binding site94ATP (UniProtKB | ChEBI)
Binding site136ADP (UniProtKB | ChEBI)
Binding site136ATP (UniProtKB | ChEBI)
Binding site1411D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site1411D-myo-inositol 1,3,4-trisphosphate (UniProtKB | ChEBI)
Binding site1421D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site1421D-myo-inositol 1,3,4-trisphosphate (UniProtKB | ChEBI)
Binding site1471D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site1471D-myo-inositol 1,3,4-trisphosphate (UniProtKB | ChEBI)
Binding site147ADP (UniProtKB | ChEBI)
Binding site147ATP (UniProtKB | ChEBI)
Binding site168ADP (UniProtKB | ChEBI)
Binding site168ATP (UniProtKB | ChEBI)
Binding site169ADP (UniProtKB | ChEBI)
Binding site169ATP (UniProtKB | ChEBI)
Binding site170ADP (UniProtKB | ChEBI)
Binding site170ATP (UniProtKB | ChEBI)
Binding site171ADP (UniProtKB | ChEBI)
Binding site171ATP (UniProtKB | ChEBI)
Binding site1791D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site194ADP (UniProtKB | ChEBI)
Binding site194ATP (UniProtKB | ChEBI)
Binding site210ADP (UniProtKB | ChEBI)
Binding site275Mg2+ 1 (UniProtKB | ChEBI)
Binding site288ADP (UniProtKB | ChEBI)
Binding site288ATP (UniProtKB | ChEBI)
Binding site2891D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site289ADP (UniProtKB | ChEBI)
Binding site289ATP (UniProtKB | ChEBI)
Binding site289Mg2+ 1 (UniProtKB | ChEBI)
Binding site289Mg2+ 2 (UniProtKB | ChEBI)
Binding site2911D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site2911D-myo-inositol 1,3,4-trisphosphate (UniProtKB | ChEBI)
Binding site291ATP (UniProtKB | ChEBI)
Binding site291Mg2+ 2 (UniProtKB | ChEBI)
Binding site2951D-myo-inositol 1,3,4,6-tetrakisphosphate (UniProtKB | ChEBI)
Binding site2951D-myo-inositol 1,3,4-trisphosphate (UniProtKB | ChEBI)

GO annotations

AspectTerm
Molecular FunctionATP binding
Molecular Functioninositol-1,3,4-trisphosphate 5-kinase activity
Molecular Functioninositol-1,3,4-trisphosphate 6-kinase activity
Molecular Functioninositol-3,4,5,6-tetrakisphosphate 1-kinase activity
Molecular Functionisomerase activity
Molecular Functionmagnesium ion binding
Biological Processinositol trisphosphate metabolic process
Biological Processphosphorylation

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Inositol-tetrakisphosphate 1-kinase
  • EC number
  • Alternative names
    • Inositol 1,3,4-trisphosphate 5/6-kinase (Inositol-triphosphate 5/6-kinase; Ins(1,3,4)P(3) 5/6-kinase) (EC:2.7.1.159) . EC:2.7.1.159 (UniProtKB | ENZYME | Rhea)

Gene names

    • Name
      ITPK1
    • ORF names
      151.t00008

Organism names

Accessions

  • Primary accession
    Q9XYQ1
  • Secondary accessions
    • Q50XK5

Proteomes

    • Identifier
    • Component
      Partially assembled WGS sequence

Organism-specific databases

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00002208381-319Inositol-tetrakisphosphate 1-kinase

Interaction

Subunit

Monomer.

Protein-protein interaction databases

Family & Domains

Features

Showing features for domain.

TypeIDPosition(s)Description
Domain98-317ATP-grasp

Sequence similarities

Belongs to the ITPK1 family.

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    319
  • Mass (Da)
    36,480
  • Last updated
    1999-11-01 v1
  • MD5 Checksum
    332E0FDD3F5431CC45E1B6FA15548E86
MTTKQTVSLFIWLPESKQKTLFISTKNHTQFELNNIIFDVTLSTELPDKEPNAIITKRTHPVGKMADEMRKYEKDHPKVLFLESSAIHDMMSSREEINALLIKNNIPIPNSFSVKSKEEVIQLLQSKQLILPFIVKPENAQGTFNAHQMKIVLEQEGIDDIHFPCLCQHYINHNNKIVKVFCIGNTLKWQTRTSLPNVHRCGIKSVDFNNQHLEDILSWPEGVIDKQDIIENSANRFGSKILEDPILLNLTSEAEMRDLAYKVRCALGVQLCGIDFIKENEQGNPLVVDVNVFPSYGGKVDFDWFVEKVALCYTEVAKI

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AF118848
EMBL· GenBank· DDBJ
AAD22969.1
EMBL· GenBank· DDBJ
Genomic DNA
DS571201
EMBL· GenBank· DDBJ
EAL46318.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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